brushes: update of deevad brushset

brushes: update of deevad brushset

Mainly little improvement here and there to make them react better,
have more linear pressure behavior, more predictible effect, or
just correction of some glitch happening sometimes with (newer?)
antialiasing and hardness. Also, I did 4 or 5 removal and sort them
a little bit differently.

Normaly, if I did well my job , most user will not see any
difference, but tools will be better for their artworks...
I changed license of the brush pack to "public domain" ( to avoid
problems with pick context, and derivative brush pack )
I didn't labelled icons with text, because most of the brush icons
visual are pretty obvious imo, and label are not adapted to each
langage ; I'm happy to have Asian user of my preset.